Means and method of making spiral binding fasteners



M. MORSE Feb. 25, 195$ MEANS AND METHOD OF MAKING SPIRAL BINDING FASTENERS Sheet Filed Oct. 11, 1966 Feb. 25, 1969 MORSE 3,429,161

MEANS AND METHOD OF MAKING SPIRAL BINDING FASTENERS Filed Oct. 11, 1966 Sheet 3 of 2 States 3,429,161 MEANS AND METHOD OF MAKING SPIRAL BINDING FASTENERS Milton Morse, Fort Lee, NJ. (41 Honecl; St., Englewood, NJ. 07631) Filed Oct. 11, 1966, Ser. No. 589,479 US. Cl. 72--88 Int. Cl. B21d 17/04; B2111 3/06; 323g 9/00 10 Claims ABSTRACT OF THE DISCLOSURE This invention relates generally to the manufacture of fasteners and screws and more particularly to novel and useful means and methods of making fasteners and screws which have a plurality of portions which deviate from their normal axes.

It is among the objects of the present invention to provide simple and efiicient means and methods for producing the said fasteners and screws whereby the same may be produced in large volume at relatively low cost to have a consequent wide sale and use.

These objects and other incidental ends and advantages will more fully appear in the progress of this disclosure and be pointed out in the appended claims.

In the drawings in which similar reference characters designate corresponding parts throughout the several views:

FIGURE 1 is a fragmentary plan view showing a first embodiment of the invention; schematically two of the stages of the present method.

FIGURE 2 is an exploded perspective view showing a pair of dies of FIGURE 1 and product.

FIGURES 3 to 5 inclusive are exploded perspective views showing modifications of the bending insert die of FIGURE 2 and their products.

FIGURE 6 is a perspective view of a modification of the stationary die of FIGURE 2 for generating a left hand spiral screw.

FIGURE 7 is a perspective view corresponding generally to FIGURE 2 but showing a modification thereof.

FIGURE 8 is a perspective view corresponding generally to FIGURE 2 but showing a modification thereof for producing a left hand spiral.

FIGURE 9 is a perspective view, corresponding generally to the upper portion of FIGURES 2 and showing another embodiment of movable die with adjustable fastener head bending cams.

FIGURES 10, 11, and 12 are perspective views showing modifications of the head bending cams of FIGURE 9.

FIGURE 13 is a plan View of a modification in which the movable die is rotary.

This invention relates to my co-pending patent application Ser. No. 649,288, filed June 27, 1967 on spiral fasteners and screws and more specifically, it relates to means for generating the same. The history of thread 3,4291% Patented Feb. 25, 1969 rolling indicates that it was first crudely demonstrated early in the 19th century. The art of thread rolling was improved over the years and has developed until now it is possible to roll very accurate threads. It has always hen the goal of manufacturers to roll threads accurately into the blank. While it is true that various types of thread rolling dies have been developed for varying the type of thread as well as varying the diameter of the screws throughout their length such as gimlet point or the wood screw, none of these dies shapes or curls the actual axis of the screws while at the same time rolling the threads into said screws.

In said co-pending application, I have described fasteners and screws which have a spiral shank. This spiral produces, in effect, a portion of a coiled spring. Screws fabricated in this fashion exert radial pressure against the walls of the confining threaded hole into which they are inserted. This radial pressure in turn produces a high degree of friction between the inserted screw and the threaded hole thus minimizing the possibility of said screw working its way lose under vibration. Other curls and shapes may also be utilized in the shank of the screw in order to obtain the same spring effect, however, I have found that the spiral tends to distribute the radial pressure throughout the entire length of the engaged threads whereas a curved screw exerts pressure at only three points. The disadvantage of this latter method is that the threads at the three high-pressure points are apt to become malformed or abraided whereas when the pressure is exerted throughout several threads, the malformation or abrasion is reduced and, consequently, the vibration-resistant characteristics are maintained even after several insertions and withdrawals of the screw. Also, I have found that a spiraled screw shows a higher resistance to dislodgement by vibration even though it is not fully inserted whereas bent screws do not exert their full effect until they are fully inserted or unless they are severely over-bent. These facts create the need for the present invention. Right-hand spirals appear to work best with right-hand threads and left-hand spirals work best with left-hand threads.

In accordance with the invention, in FIGURE 2 there is shown a first die 12 and a second die 14. In the thread rolling art these are normally respectively stationary and movable and over the greater part of their working surfaces 16 and 18 respectively are provided with the usual thread forming contours, to produce the desired thread forms and pitches. Dies 112 and 14 in the position shown have blank entering areas 20 and 22 and blank discharging zones 24 and 26 respectively. Area 24 is provided with a depression 28 with a bending boundary edge 30, while zone 26 may be provided with a deviation producing projection 32. It will be apparent that these formations are relative and the motions of the dies and the proj ction and depression may be transposed as required. The surface of the finished connector is the product of the surface of the dies 12 and 14 so that for example, smooth die surfaces will produce burnished spiral pins.

Since the required amount of spiral is correlated to the length of the finished screw, it reduces die cost to have four corners of the stationary die 12 reli ved and used in four positions. Thus, for example, depression 28 and its bending edge 30 may bend 1"1%" length screws, depression 28x and edge Stlx may bend %"1" length screws, depression 28y and its edge may bend /2"%" 3 length screws, and depression 282 and its edge may bend At /2 l ngth screws.

Turning to FIGURES 1 and 2, the stationary die 12 of the pair of thread rolling dies, is constructed to produce a right-handed spiral. To describe the function of die 12, I will discuss the right-hand spiral first. In FIG- URE 1, it can be seen that the entering unthreaded lank 34 is captured between the stationary die 12 and the moving die 14 at the start of the thread rolling stroke. During the thread rolling stroke the blank 34 mak s a number of revolutions as it moves across the surface 16 of the stationary die. The finished threaded part 36 emerges from between the two dies as indicated by the arrow 38. The upper corner 40 of the stationary die is r lieved and the pressure of the moving die bends the upper portion of the blank 34 slightly and progressively on the boundary bending edge 30 as it becomes no longer supported by the stationary die 12. As blank 34 rolls further along to the left as viewed in FIGS. 1 and 2, the next portion of the screw is also bent. This bending continu s through one complete revolution of the screw resulting in a spiraling of the screw body. It will be seen that altering the dimensions of the depression 28 and edge 30 will vary the number of revolutions of screw 36 during the bending process and would result in several spirals being generated within th length of the screw. A smaller depression 28 would result in less than one complete spiral.

In FIGURE 6 corresponding parts have the same reference character with the addition of the sufiix b. The depression 28b is reversed and produces a left-hand spiral. Thus, it can be seen that a left-hand spiral can be generated on a right-hand or left-hand thread or a righthand spiral may be generated on a left hand or right hand thread.

Similarly, modifications may also be made to the moving die so as to produce a left hand spiral.

In certain cases, I have found it desirable to provide an insert or projection 32 on the moving die in order to increase or vary the deformation by driving the emerging part deeper into the depression or recessed portions 28 of the stationary die '12. Variations of these ins rts are shown in FIGURES 3, 4, and of the drawings with corresponding reference characters with the suffix d, e, and f. It may also be seen that curves and spirals can be produced in any portion of the axis of the screw by locating these modifications and inserts at different areas in the dies.

Inserts or deviation producing projections 32., 320?, 32e, and 32 bear upon the threaded portion of a screw being treated, not the head of th screw, and are useful on polygonal or flat head screws. Thus, projection 32 produces a spiral; projection 32d produces a bent tip 46d; projection 32c produces a middle bend -48e; and projection 32 produces a plurality of bends SW and 52f, which may be in an S arrangement.

In the modification shown in FIGURE 7, certain of the corresponding parts are given the same reference characters with the suffix g and this form differs principally from the structure of FIGURE 2 in that the projection 32g is fabricated by cutting away at 31g and 33g to form a finger which is bent out, the thread forming surfac thereof 18g eing gently curved to preserve the thread shape on the finished screw 36.

In the modification shown in FIGURE 8 corresponding parts have the suffix h. This form differs from the structure of FIGURE 2 in that the depression 28h is located at the trailing zone 26]: of the moving die 1411 while the projection 32h on the stationary die 12h acting as a bending cam, co-acts with depression 2811 to produce a left-hand spiral 58h in the screw 3612. Whether the screw 3611 has right hand threads l'lh or left hand threads will dep nd solely on the surfaces 16k and 18k as is well known in the art.

In FIGURE 9, corresponding parts have sufiix i, and this structure differs from FIGURE 2 in that projection 321' is constructed and arranged to bear upon the heads of the screws being treated, and does not engage the shanks of said screws. This use is not suggested on soft, polygonal, or flat headed screws.

As is known in the art, and indicated in FIGURE 2, both principal faces of the dies may have working surfaces and dies may be changed in relative position to use fresh surfaces when wear takes place. Thus, the elongated insert 601' may have multiple projections 321' and 331' coacting with the respective working surfaces 18i and 191' and slidably engaged by flange 621' in groove 641'. Similarly after inversion, insert 601' may coact with groove 661'. The insert 691' is longitudinally adjustable with respect to die Hi to produce different shapes and is retained in position by die clamps 68 (FIG. I). FIGURES 10, 11, and 12 have corresponding suffixes j, k, and i. Thus projections 32i and 331' are spiraling head cams; projections 46j and 47 are tip bending cams; projections 48k and 49k are middle bending head cams; and projections 50c, 52c, and Sle, 532 are double bending head cams.

In FIGURE 13 corresponding surfaces have the suffix m. Rotary die 14111 has a plurality of working surfaces 18m which coact with the stationary die 12m, the projections 32m co-acting with depression 28m.

Some of the finer points of these modifications include the rounding off and smoothing out of the thread rolling ribs so that there will be no scoring of the threads on the emerging screws. Other considerations include shimming the stationary die or the moving die so that there will be no taper in the threaded portion of the screw. This taper could result from the fact that less and less of the screw is captured between the two thread rolling dies as the screw proceeds towards the finishing end of said thread rolling die.

I wish it to be understood that I do not desire to be limited to the exact details shown and described for obvious modifications will occur to a person skilled in the art to which the present invention relates.

I claim:

1. For use with a blank to be treated, first and second thread rolling dies having working surfaces and movable with respect to each other with said blank disposed between them; one of said dies having a depression; the other of said dies having a corresponding projection; whereby as said blank is rolled between said dies, it enters said depression and is bent so that at least a portion of said blank is deviated from its central axis.

2. Structure as claimed in claim 1 in which the projection has a development of a thread on its working face.

3. Structure as claimed in claim 1 in which on the die having the depression, there is a bending edge between the normal working face of the die and the depression, said edge being disposed at an angle with respect to the line of motion of the movable die.

4. Structure as claimed in claim 1 in which said projection is adjustable in position with respect to the die upon which it is mounted.

5. Structure as claimed in claim 1 in which one of the dies has a plurality of deviation-producing projections coacting with said depression.

6. Structure as claimed in claim 1 in which each die has developed thread-working surfaces and said surfaces extend into the depression.

7. Structure as claimed in claim 1 in which the blank has a head, and in which one die has a projection constructed and arranged to contact said head and bend the blank.

8. Structure as claimed in claim 1 in which the die faces have thread forming faces for forming a thread in a predetermined direction and the depression is constructed and arranged to produce a spiral deviation in the same direction as the thread.

9. Structure as claimed in claim 1 in which the die faces have thread-forming surfaces which form a thread in a predetermined direction and the depression is constructed and arranged to produce a spiral deviation in a direction opposite the direction of the thread.

10. In the method of making an elongated fastening element from a blank: providing a die with a depression; rolling said blank along said die; and pressing said blank into said depression; whereby the blank is bent to produce a fastening element at least a portion of Which is deviated from the normal axis of the fastening element.

References Cited UNITED STATES PATENTS MILTON S. MEHR, Primary Examiner.

US. Cl. X.R. 72-469; 102 

